Merge pull request #40 from jcoreio/typescript

feat: convert project to typescript

chore: upgrade toolchain to fix semantic-release ENOENT error in CI

fix: include .md files in published package

chore: update build toolchain and config

fix: flow errors

fix: exclude config-chain dependency from flow type checking

fix: update exports to fix mismatch between require / import declarat…

…ions

build: upgrade semantic-release

fix(setIn): fix path flow type

docs(README.md): add example require statements [ci skip]